trichlorophosphate in 1,2-dichloro-ethane T=20°C; 16 h;

2,6-dimethylpyridine N-oxide; borate(1-), tetrafluoro-,hydrogen (1:1) ethane, 1,1'-oxybis- in 1,4-dioxane T=80°C; 3 h; Reagent/catalystTime;

1.1: sulfur; morpholine; p-toluenesulfonic acid / 8 h / 120 - 130 °C 1.2: 64 percent / sodium hydroxide; tetrabutylammonium bromide / H2O / 8 h / 100 °C 2.1: 85 percent / phosphorus oxychloride / 1,2-dichloro-ethane / 16 h / 20 °C View Scheme

1: n-butyllithium / diethyl ether / 4 h / -78 - -40 °C / |Schlenk technique; |Inert atmosphere 2: 2,6-dimethylpyridine N-oxide; borate(1-), tetrafluoro-,hydrogen (1:1) ethane, 1,1'-oxybis- / 1,4-dioxane / 3 h / 80 °C View Scheme

1: sodium hydroxide / dimethyl sulfoxide / 2 h / 20 °C 2: n-butyllithium / diethyl ether / 4 h / -78 - -40 °C / |Schlenk technique; |Inert atmosphere 3: 2,6-dimethylpyridine N-oxide; borate(1-), tetrafluoro-,hydrogen (1:1) ethane, 1,1'-oxybis- / 1,4-dioxane / 3 h / 80 °C View Scheme

potassium hydroxide; copper 1) H20, 70 deg C, 20 min 2) reflux, 9 h; Yield given. Multistep reaction;

1: 66 percent / pyridine hydrochloride / 3 h / 180 - 190 °C 2: potassium hydroxide / ethanol / 15 h / 20 °C / pH 8 View Scheme

pyridine hydrochloride T=180 - 190°C; 3 h;